Devices, systems, and methods for vessel assessment and intervention recommendation

ABSTRACT

Devices, systems, and methods of evaluating risk associated with a condition of the vessel and providing an objective intervention recommendation based on the evaluated risk are disclosed. The method includes steps of obtaining physiologic measurements from a first instrument and a second instrument positioned within the vessel of the patient while the second instrument is moved longitudinally through the vessel from a first position to a second position, obtaining image data from an image of a vessel system, co-registering the physiologic measurements with the image data to produce co-registered physiologic measurements, and determining whether to perform a first surgical procedure or a second surgical procedure, wherein the determining is based on the co-registered physiologic measurements. Other associated methods, systems, and devices are also provided herein.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to and the benefit of the U.S.Provisional Patent Application No. 62/089,039, filed Dec. 8, 2014, whichis hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to the assessment of vesselsand, in particular, the assessment of the severity of a blockage orother restriction to the flow of fluid through a vessel and thetreatment thereof. Aspects of the present disclosure are particularlysuited for evaluation of biological vessels in some instances. Forexample, some particular embodiments of the present disclosure arespecifically configured for the evaluation of human blood vessels.

BACKGROUND

A currently accepted technique for assessing the severity of a stenosisin a blood vessel, including ischemia causing lesions, is fractionalflow reserve (FFR). FFR is a calculation of the ratio of a distalpressure measurement (taken on the distal side of the stenosis) relativeto a proximal pressure measurement (taken on the proximal side of thestenosis). FFR provides an index of stenosis severity that allowsdetermination as to whether the blockage limits blood flow within thevessel to an extent that treatment is required. The normal value of FFRin a healthy vessel is 1.00, while values less than about 0.80 aregenerally deemed significant and require treatment. Common treatmentoptions include percutaneous coronary intervention (PCI or angioplasty),stenting, or coronary artery bypass graft (CABG) surgery. As with allmedical procedures, certain risks are associated with PCI, stenting, andCABG procedures. In order for a surgeon to make a better-informeddecision regarding treatment options, additional information about therisk and likelihood of success associated with the treatment options isneeded.

The severity of a stenosis is sometimes observed visually and roughlyestimated based on experience. A patient's vasculature can be visualizedusing angiography. However, the locations of stenoses in a vessel can bedifficult to visualize in a black and white angiographic image. The useof pressure data can improve the interpretation of information gleanedfrom an angiogram. Moreover, the severity of stenosis can also be betterunderstood when efficiently visualized in relation to an angiographicimage in connection with such data. Further, a more complete diagnosisof the patient can be made when the effects of both focal and diffusestenoses are evaluated.

Accordingly, there remains a need for improved devices, systems, andmethods for assessing the severity of a blockage in a vessel and, inparticular, a stenosis in a blood vessel and for providing treatmentbest suited to the blockage in the vessel or blockages in the vesselsystem. Further, there remains a need for improved devices, systems, andmethods of objectively evaluating risk associated with one or moretreatment options and the likelihood of success those treatment optionsfor the particular vessel.

SUMMARY

Embodiments of the present disclosure are directed to providing anobjective recommendation of a treatment for a patient. One generalaspect includes a method of recommending an intervention for a patient,including: co-registering a set of pressure measurements taken within avessel system of the patient with image data of the vessel system toproduce co-registered pressure measurements; calculating an image-baseddisease quantification score from the image data of the vessel system;modifying the image-based disease quantification score based onco-registered physiologic measurements to produce a functional diseasequantification score; determining whether to perform a percutaneouscoronary intervention or a coronary artery bypass graft(CABG), where thedetermining is based on the functional disease quantification score; anddisplaying an indication of the recommended intervention on a display.

Implementations may include one or more of the following features. Themethod where the indication of the recommended intervention identifies aCABG procedure when the functional disease quantification score is abovea threshold. The method where the image-based disease quantificationscore includes a SYNTAX score and the function disease quantificationscore includes a functional SYNTAX score. The method where determiningwhether to perform the first surgical procedure or the second surgicalprocedure includes: interpreting, by a processing unit, the image dataof the vessel system; identifying one or more lesions within the vesselsystem; and extracting, from the image data of the vessel system,physiology information.

Another general aspect includes a method of evaluating a vessel systemof a patient to recommend an intervention for the patient, the methodincluding: obtaining physiologic measurements from a first instrumentand a second instrument positioned within the vessel of the patientwhile the second instrument is moved longitudinally through the vesselfrom a first position to a second position; obtaining image data from animage of a vessel system; co-registering the physiologic measurementswith the image data to produce co-registered physiologic measurements;and calculating a disease quantification score, the diseasequantification score indicating whether to perform a first surgicalprocedure or a second surgical procedure, where the calculating is basedon the co-registered physiologic measurements.

Implementations may include one or more of the following features. Themethod where the image is an extravascular image. The method whereco-registering the physiologic measurements with the image data toprovide co-registered physiological measurements includes: associating,in a data file, each physiology measurement with a location within thevessel system. The method may also include identifying a correspondinglocation for each physiology measurement within the image data. Themethod may also include associating, in a co-registered physiologicmeasurements data file, each physiology measurement with itscorresponding location within the image of the vessel system.

Implementations of the described techniques may include hardware, amethod or process, or computer software on a computer-accessible medium.Other embodiments of this aspect include corresponding computer systems,apparatus, and computer programs recorded on one or more computerstorage devices, each configured to perform the actions of the methods.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrative embodiments of the present disclosure will be describedwith reference to the accompanying drawings, of which:

FIG. 1 is a diagrammatic perspective view of a vessel having a stenosisaccording to an embodiment of the present disclosure.

FIG. 2 is a diagrammatic, partial cross-sectional perspective view of aportion of the vessel of FIG. 1 taken along section line 2-2 of FIG. 1.

FIG. 3 is a diagrammatic, partial cross-sectional perspective view ofthe vessel of FIGS. 1 and 2 with instruments positioned thereinaccording to an embodiment of the present disclosure.

FIG. 4 is a diagrammatic, schematic view of a system according to anembodiment of the present disclosure.

FIG. 5 is a stylized image of a patient's vasculature as seen in anangiogram image according to an embodiment of the present disclosure.

FIG. 6 is an annotated version of a user interface according to anembodiment of the present disclosure.

FIG. 7 is a series of stylized images of a vessel illustratingclassification of vessel obstructions according to an embodiment of thepresent disclosure.

FIG. 8A is a stylized image of a patient's vasculature as seen in a userinterface according to an embodiment of the present disclosure.

FIG. 8B is a stylized image of a patient's vasculature as seen inanother user interface according to an embodiment of the presentdisclosure.

FIG. 9 is a flow diagram of a method for recommending an interventionfor a patient according to an embodiment of the present disclosure.

FIG. 10 is a flow diagram of another method for recommending anintervention for a patient according to an embodiment of the presentdisclosure.

These drawings may be better understood by reference to the followingdetailed description.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of thepresent disclosure, reference will now be made to the embodimentsillustrated in the drawings, and specific language will be used todescribe the same. It is nevertheless understood that no limitation tothe scope of the disclosure is intended. Any alterations and furthermodifications to the described devices, systems, and methods, and anyfurther application of the principles of the present disclosure arefully contemplated and included within the present disclosure as wouldnormally occur to one skilled in the art to which the disclosurerelates. In particular, it is fully contemplated that the features,components, and/or steps described with respect to one embodiment may becombined with the features, components, and/or steps described withrespect to other embodiments of the present disclosure. For the sake ofbrevity, however, the numerous iterations of these combinations will notbe described separately.

Physiologic measurement data and the coronary angiogram typically behaveas complementary, yet segregated sources of information. The coronaryangiogram has been used to make treatment decisions. More recently,physiological data (including, but not limited to, pressure and/or flowmeasurements, both at hyperemia and rest) have shown that betterdecisions can be made based on the severity of a blockage by measuringthe change in underlying physiological conditions from the beginning ofa target artery to the end. Treating a patient based on the severity ofthis change or delta has shown to improve outcomes and reduce waste fromunnecessary procedures. In one or more aspects of the presentdisclosure, the physiological data, as collected real-time, is linked orco-registered to a schematic of the coronary arteries or an angiogram.The data may also be visually depicted in a way that allows a clinicianto interact and assess where severity changes, by sliding markings asplaced on the image of the vessel and correlated with the collectedphysiological data. One or more embodiments described herein are alsoable to automatically make updates to the visual depiction based on thecollected data as processed according to a risk calculator to provide arecommendation such as a particular intervention for a patient. Forexample, the data may be processed to provide an objectiverecommendation of whether to perform a percutaneous coronaryintervention (PCI) or a coronary artery bypass graft (CABG) surgery.

One aspect of the present disclosure includes using a model of thepatient's vasculature, obtained from angiography, to automaticallycalculate a disease quantification score. In this disclosure, the SYNTAXscore is used as one example of such a disease quantification score.Other disease quantification scores may be used within the scope of thisdisclosure. One aspect of the present disclosure includes super-imposingreal-time collected pressure and/or flow data (or other physiologicdata) onto an angiogram, or a schematic of anatomy and representing thedata in a way that helps a clinician determine how/where to intervene(including but not limited to using data to determine where to performgrafts (CABG planning) and PCI planning). One aspect of the presentdisclosure includes utilizing the collected pressure and/or flow data toautomatically update the disease quantification score, thereby providinga functional disease quantification score. In some embodiments, thecollected physiology data may include real-time data obtained during aprocedure. One aspect of the present disclosure includes using thepressure, flow or other physiologic data with a computational algorithmto predict probabilities of graft patency and perfusion improvementduring coronary artery bypass grafting (CABG). One aspect of the presentdisclosure includes processing the super-imposed physiologic data toisolate “regions of interest” where severity of physiologic data changessubstantially for the purposes of determining how/where to intervene.One aspect of the present disclosure includes using thesystem-determined regions of interest to calculate a functional diseasequantification score. Whether to perform a surgical procedure can beevaluated based on one or more of physiologic measurements, an image ofthe vessel with one or more visualizations, and relevant risk andperfusion calculations. A recommendation between one or moreintervention options may be determined by the functional diseasequantification score and presented to the clinician in a user interface.

In some embodiments, PCI planning is facilitated by the graphicaloverlay of physiologic data and the ability to add/delete and dragmarkings that allow the user to size and isolate blockages. Using afeature of a guide catheter and/or the guide wire as a calibrated andknown length permits using these markings and co-registered physiologicdata to estimate lesion lengths. These data can be inputted into a riskcalculator including but not limited to a functional SYNTAX score. Theuse of the markings, length, and physiology data permit theinterventionalist to plan a percutaneous coronary intervention wherebythe number of stents and length of stents can be estimated. In someembodiments, the system may provide such a plan according to thefunctional disease quantification score and associated data.

In some embodiments, CABG planning is facilitated by the graphicaloverlay of physiologic data and the ability to add/delete and drag themarkings that allow the user to size and isolate the blockages. Inplanning a bypass surgery (CABG), the data allows the physician toidentify where on the artery the disease starts and stops. In someembodiments, the system may provide recommendations regarding theplacement of such grafts. This results in a CABG plan, where the idealplacement of a graph can be determined and the prediction of graftpatency and perfusion benefit can be identified to support decisionmaking. The benefit of this is optimizing outcomes like graft patencyand reducing costs like unnecessary grafting and time.

Referring to FIGS. 1 and 2, shown therein is a vessel 100 having astenosis according to an embodiment of the present disclosure. In thatregard, FIG. 1 is a diagrammatic perspective view of the vessel 100,while FIG. 2 is a partial cross-sectional perspective view of a portionof the vessel 100 taken along section line 2-2 of FIG. 1. Referring morespecifically to FIG. 1, the vessel 100 includes a proximal portion 102and a distal portion 104. A lumen 106 extends along the length of thevessel 100 between the proximal portion 102 and the distal portion 104.In that regard, the lumen 106 is configured to allow the flow of fluidthrough the vessel. In some instances, the vessel 100 is a blood vessel.In some particular instances, the vessel 100 is a coronary artery. Insuch instances, the lumen 106 is configured to facilitate the flow ofblood through the vessel 100.

As shown, the vessel 100 includes a stenosis 108 between the proximalportion 102 and the distal portion 104. The stenosis 108 is generallyrepresentative of any blockage or other structural arrangement thatresults in a restriction to the flow of fluid through the lumen 106 ofthe vessel 100. Embodiments of the present disclosure are suitable foruse in a wide variety of vascular applications, including withoutlimitation coronary, peripheral (including but not limited to lowerlimb, carotid, and neurovascular), renal, and/or venous. Where thevessel 100 is a blood vessel, the stenosis 108 may be a result of plaquebuildup, including without limitation plaque components such as fibrous,fibro-lipidic (fibro fatty), necrotic core, calcified (dense calcium),blood, fresh thrombus, and mature thrombus. Generally, the compositionof the stenosis will depend on the type of vessel being evaluated. Inthat regard, it is understood that the concepts of the presentdisclosure are applicable to virtually any type of blockage or othernarrowing of a vessel that results in decreased fluid flow.

Referring more particularly to FIG. 2, the lumen 106 of the vessel 100has a diameter 110 proximal of the stenosis 108 and a diameter 112distal of the stenosis. In some instances, the diameters 110 and 112 aresubstantially equal to one another. In that regard, the diameters 110and 112 are intended to represent healthy portions, or at leasthealthier portions, of the lumen 106 in comparison to stenosis 108.Accordingly, these healthier portions of the lumen 106 are illustratedas having a substantially constant cylindrical profile and, as a result,the height or width of the lumen has been referred to as a diameter.However, it is understood that in many instances these portions of thelumen 106 will also have plaque buildup, a non-symmetric profile, and/orother irregularities, but to a lesser extent than stenosis 108 and,therefore, will not have a cylindrical profile. In such instances, thediameters 110 and 112 are understood to be representative of a relativesize or cross-sectional area of the lumen and do not imply a circularcross-sectional profile.

As shown in FIG. 2, stenosis 108 includes plaque buildup 114 thatnarrows the lumen 106 of the vessel 100. In some instances, the plaquebuildup 114 does not have a uniform or symmetrical profile, makingangiographic evaluation of such a stenosis unreliable. In theillustrated embodiment, the plaque buildup 114 includes an upper portion116 and an opposing lower portion 118. In that regard, the lower portion118 has an increased thickness relative to the upper portion 116 thatresults in a non-symmetrical and non-uniform profile relative to theportions of the lumen proximal and distal of the stenosis 108. As shown,the plaque buildup 114 decreases the available space for fluid to flowthrough the lumen 106. In particular, the cross-sectional area of thelumen 106 is decreased by the plaque buildup 114. At the narrowest pointbetween the upper and lower portions 116, 118 the lumen 106 has a height120, which is representative of a reduced size or cross-sectional arearelative to the diameters 110 and 112 proximal and distal of thestenosis 108. Note that the stenosis 108, including plaque buildup 114is exemplary in nature and should be considered limiting in any way. Inthat regard, it is understood that the stenosis 108 has other shapesand/or compositions that limit the flow of fluid through the lumen 106in other instances. While the vessel 100 is illustrated in FIGS. 1 and 2as having a single stenosis 108 and the description of the embodimentsbelow is primarily made in the context of a single stenosis, it isnevertheless understood that the devices, systems, and methods describedherein have similar application for a vessel having multiple stenosisregions.

Referring now to FIG. 3, the vessel 100 is shown with instruments 130and 132 positioned therein according to an embodiment of the presentdisclosure. In general, instruments 130 and 132 may be any form ofdevice, instrument, or probe sized and shaped to be positioned within avessel. In the illustrated embodiment, instrument 130 is generallyrepresentative of a guide wire, while instrument 132 is generallyrepresentative of a catheter. In that regard, instrument 130 extendsthrough a central lumen of instrument 132. However, in otherembodiments, the instruments 130 and 132 take other forms. In thatregard, the instruments 130 and 132 are of similar form in someembodiments. For example, in some instances, both instruments 130 and132 are guide wires. In other instances, both instruments 130 and 132are catheters. On the other hand, the instruments 130 and 132 are ofdifferent form in some embodiments, such as the illustrated embodiment,where one of the instruments is a catheter and the other is a guidewire. Further, in some instances, the instruments 130 and 132 aredisposed coaxial with one another, as shown in the illustratedembodiment of FIG. 3. In other instances, one of the instruments extendsthrough an off-center lumen of the other instrument. In yet otherinstances, the instruments 130 and 132 extend side-by-side. In someparticular embodiments, at least one of the instruments is as arapid-exchange device, such as a rapid-exchange catheter. In suchembodiments, the other instrument is a buddy wire or other deviceconfigured to facilitate the introduction and removal of therapid-exchange device. Further still, in other instances, instead of twoseparate instruments 130 and 132 a single instrument is utilized. Insome embodiments, the single instrument incorporates aspects of thefunctionalities (e.g., data acquisition) of both instruments 130 and132.

Instrument 130 is configured to obtain diagnostic information about thevessel 100. In that regard, the instrument 130 includes one or moresensors, transducers, and/or other monitoring elements configured toobtain the diagnostic information about the vessel. The diagnosticinformation includes one or more of pressure, flow (velocity), images(including images obtained using ultrasound (e.g., IVUS), OCT, and/orother imaging techniques), temperature, and/or combinations thereof. Theone or more sensors, transducers, and/or other monitoring elements arepositioned adjacent a distal portion of the instrument 130 in someinstances. In that regard, the one or more sensors, transducers, and/orother monitoring elements are positioned less than 30 cm, less than 10cm, less than 5 cm, less than 3 cm, less than 2 cm, and/or less than 1cm from a distal tip 134 of the instrument 130 in some instances. Insome instances, at least one of the one or more sensors, transducers,and/or other monitoring elements is positioned at the distal tip of theinstrument 130.

The instrument 130 includes at least one element configured to monitorpressure within the vessel 100. The pressure monitoring element can takethe form a piezo-resistive pressure sensor, a piezo-electric pressuresensor, a capacitive pressure sensor, an electromagnetic pressuresensor, a fluid column (the fluid column being in communication with afluid column sensor that is separate from the instrument and/orpositioned at a portion of the instrument proximal of the fluid column),an optical pressure sensor, and/or combinations thereof. In someinstances, one or more features of the pressure monitoring element areimplemented as a solid-state component manufactured using semiconductorand/or other suitable manufacturing techniques. Examples of commerciallyavailable guide wire products that include suitable pressure monitoringelements include, without limitation, the Verrata® pressure guide wire,the PrimeWire Prestige® PLUS pressure guide wire, and the ComboWire® XTpressure and flow guide wire, each available from Volcano Corporation,as well as the PressureWire™ Certus guide wire and the PressureWire™Aeris guide wire, each available from St. Jude Medical, Inc. Generally,the instrument 130 is sized such that it can be positioned through thestenosis 108 without significantly impacting fluid flow across thestenosis, which would impact the distal pressure reading. Accordingly,in some instances the instrument 130 has an outer diameter of 0.018″ orless. In some embodiments, the instrument 130 has an outer diameter of0.014″ or less. In other embodiments, the instrument 130 has an outerdiameter of 0.035″ or less.

Instrument 132 is also configured to obtain diagnostic information aboutthe vessel 100. In some instances, instrument 132 is configured toobtain the same diagnostic information as instrument 130. In otherinstances, instrument 132 is configured to obtain different diagnosticinformation than instrument 130, which may include additional diagnosticinformation, less diagnostic information, and/or alternative diagnosticinformation. The diagnostic information obtained by instrument 132includes one or more of pressure, flow (velocity), images (includingimages obtained using ultrasound (e.g., IVUS), OCT, and/or other imagingtechniques), temperature, and/or combinations thereof. Instrument 132includes one or more sensors, transducers, and/or other monitoringelements configured to obtain this diagnostic information. In thatregard, the one or more sensors, transducers, and/or other monitoringelements are positioned adjacent a distal portion of the instrument 132in some instances. In that regard, the one or more sensors, transducers,and/or other monitoring elements are positioned less than 30 cm, lessthan 10 cm, less than 5 cm, less than 3 cm, less than 2 cm, and/or lessthan 1 cm from a distal tip 136 of the instrument 132 in some instances.In some instances, at least one of the one or more sensors, transducers,and/or other monitoring elements is positioned at the distal tip of theinstrument 132.

Similar to instrument 130, instrument 132 also includes at least oneelement configured to monitor pressure within the vessel 100. Thepressure monitoring element can take the form a piezo-resistive pressuresensor, a piezo-electric pressure sensor, a capacitive pressure sensor,an electromagnetic pressure sensor, a fluid column (the fluid columnbeing in communication with a fluid column sensor that is separate fromthe instrument and/or positioned at a portion of the instrument proximalof the fluid column), an optical pressure sensor, and/or combinationsthereof. In some instances, one or more features of the pressuremonitoring element are implemented as a solid-state componentmanufactured using semiconductor and/or other suitable manufacturingtechniques. Currently available catheter products suitable for use withone or more of Siemens AXIOM Sensis, Mennen Horizon XVu, and PhilipsXper IM Physiomonitoring 5 and include pressure monitoring elements canbe utilized for instrument 132 in some instances.

In accordance with aspects of the present disclosure, at least one ofthe instruments 130 and 132 is configured to monitor a pressure withinthe vessel 100 distal of the stenosis 108 and at least one of theinstruments 130 and 132 is configured to monitor a pressure within thevessel proximal of the stenosis. In that regard, the instruments 130,132 are sized and shaped to allow positioning of the at least oneelement configured to monitor pressure within the vessel 100 to bepositioned proximal and/or distal of the stenosis 108 as necessary basedon the configuration of the devices. In that regard, FIG. 3 illustratesa position 138 suitable for measuring pressure distal of the stenosis108. In that regard, the position 138 is less than 5 cm, less than 3 cm,less than 2 cm, less than 1 cm, less than 5 mm, and/or less than 2.5 mmfrom the distal end of the stenosis 108 (as shown in FIG. 2) in someinstances. FIG. 3 also illustrates a plurality of suitable positions formeasuring pressure proximal of the stenosis 108. In that regard,positions 140, 142, 144, 146, and 148 each represent a position that issuitable for monitoring the pressure proximal of the stenosis in someinstances. In that regard, the positions 140, 142, 144, 146, and 148 arepositioned at varying distances from the proximal end of the stenosis108 ranging from more than 20 cm down to about 5 mm or less. Generally,the proximal pressure measurement will be spaced from the proximal endof the stenosis. Accordingly, in some instances, the proximal pressuremeasurement is taken at a distance equal to or greater than an innerdiameter of the lumen of the vessel from the proximal end of thestenosis. In the context of coronary artery pressure measurements, theproximal pressure measurement is generally taken at a position proximalof the stenosis and distal of the aorta, within a proximal portion ofthe vessel. However, in some particular instances of coronary arterypressure measurements, the proximal pressure measurement is taken from alocation inside the aorta. In other instances, the proximal pressuremeasurement is taken at the root or ostium of the coronary artery.

In some embodiments, at least one of the instruments 130 and 132 isconfigured to monitor pressure within the vessel 100 while being movedthrough the lumen 106. In some instances, instrument 130 is configuredto be moved through the lumen 106 and across the stenosis 108. In thatregard, the instrument 130 is positioned distal of the stenosis 108 andmoved proximally (i.e., pulled back) across the stenosis to a positionproximal of the stenosis in some instances. In other instances, theinstrument 130 is positioned proximal of the stenosis 108 and moveddistally across the stenosis to a position distal of the stenosis.Movement of the instrument 130, either proximally or distally, iscontrolled manually by medical personnel (e.g., hand of a surgeon) insome embodiments. In other embodiments, movement of the instrument 130,either proximally or distally, is controlled automatically by a movementcontrol device (e.g., a pullback device, such as the Trak Back® IIDevice available from Volcano Corporation). In that regard, the movementcontrol device controls the movement of the instrument 130 at aselectable and known speed (e.g., 2.0 mm/s, 1.0 mm/s, 0.5 mm/s, 0.2mm/s, etc.) in some instances.

In some embodiments, because the movement of the instrument 130 isselectable and known, the position of the distal tip 134 relative to thepatient's vasculature may be estimated with sufficient precision toprovide for the co-registration of data obtained by the instrument 130with a computer model of the patient's vasculature obtained fromangiography. Movement of the instrument 130 through the vessel iscontinuous for each pullback or push through, in some instances. Inother instances, the instrument 130 is moved step-wise through thevessel (i.e., repeatedly moved a fixed amount of distance and/or a fixedamount of time). Some aspects of the visual depictions discussed beloware particularly suited for embodiments where at least one of theinstruments 130 and 132 is moved through the lumen 106. Further, in someparticular instances, aspects of the visual depictions discussed beloware particularly suited for embodiments where a single instrument ismoved through the lumen 106, with or without the presence of a secondinstrument. In other embodiments, image-based co-registration may beperformed. For example, fluoroscopy may be used to observe avisualization agent introduced into the vasculature of the patient. Thetip of the instrument 130 may be used to contact a number of pointswithin the vasculature to establish the location of those points usingfluoroscopy. Additionally, radiopaque markers may be embedded in theinstrument 130 to enable tracking.

In some instances, the instruments 130 and 132 may be used to provideinstantaneous wave-free ratio (iFR®) measurements instead of, or inaddition, to traditional FFR measurements as described above. Such iFRmeasurements may be obtained using products produced by the VolcanoCorporation. In some embodiments, FFR data and iFR data may be usedtogether to assess the patient. The FFR or iFR data may be used todetermine whether the disease is focal or diffuse. In some embodiments,the pullback curve based on FFR or iFR may be used to determine whetherthe patient's disease is focal or diffuse.

Referring now to FIG. 4, shown therein is a system 150 according to anembodiment of the present disclosure. In that regard, FIG. 4 is adiagrammatic, schematic view of the system 150. As shown, the system 150includes an instrument 152. In that regard, in some instances instrument152 is suitable for use as at least one of instruments 130 and 132discussed above. Accordingly, in some instances the instrument 152includes features similar to those discussed above with respect toinstruments 130 and 132 in some instances. In the illustratedembodiment, the instrument 152 is a guide wire having a distal portion154 and a housing 156 positioned adjacent the distal portion. In thatregard, the housing 156 is spaced approximately 3 cm from a distal tipof the instrument 152. The housing 156 is configured to house one ormore sensors, transducers, and/or other monitoring elements configuredto obtain the diagnostic information about the vessel. In theillustrated embodiment, the housing 156 contains at least a pressuresensor configured to monitor a pressure within a lumen in which theinstrument 152 is positioned. A shaft 158 extends proximally from thehousing 156. A torque device 160 is positioned over and coupled to aproximal portion of the shaft 158. A proximal end portion 162 of theinstrument 152 is coupled to a connector 164. A cable 166 extends fromconnector 164 to a connector 168. In some instances, connector 168 isconfigured to be plugged into an interface 170. In that regard,interface 170 is a patient interface module (PIM) in some instances. Insome instances, the cable 166 is replaced with a wireless connection. Inthat regard, it is understood that various communication pathwaysbetween the instrument 152 and the interface 170 may be utilized,including physical connections (including electrical, optical, and/orfluid connections), wireless connections, and/or combinations thereof.

The interface 170 is communicatively coupled to a computing device 172via a connection 174. Computing device 172 is generally representativeof any device suitable for performing the processing and analysistechniques discussed within the present disclosure. In some embodiments,the computing device 172 includes a processor, random access memory, anda storage medium. In that regard, in some particular instances thecomputing device 172 is programmed to execute steps associated with thedata acquisition and analysis described herein. Accordingly, it isunderstood that any steps related to data acquisition, data processing,instrument control, and/or other processing or control aspects of thepresent disclosure may be implemented by the computing device usingcorresponding instructions stored on or in a non-transitorycomputer-readable medium accessible by the computing device. In someinstances, the computing device 172 is a console device. In someparticular instances, the computing device 172 is similar to the s5™Imaging System or the s5i® Imaging System, each available from VolcanoCorporation. In some instances, the computing device 172 is portable(e.g., handheld, on a rolling cart, etc.). Further, it is understoodthat in some instances the computing device 172 comprises a plurality ofcomputing devices. In that regard, it is particularly understood thatthe different processing and/or control aspects of the presentdisclosure may be implemented separately or within predefined groupingsusing a plurality of computing devices. Any divisions and/orcombinations of the processing and/or control aspects described belowacross multiple computing devices are within the scope of the presentdisclosure.

The computing device 172 may acquire data from many different sources.For example, as described herein the computing device 172 maycommunicate through the interface 170 to collect physiologicalmeasurements from instruments, such as instruments 130 and 132,positioned within a patient's vasculature. Additionally, the computingdevice 172 may include a network interface card or similar interface tocommunicate with a network 180. The computing device 172 may accessangiography data to produce a model of the patient's vasculature or mayaccess a pre-computed model. For example, an existing model of thepatient's vasculature may have been generated based on previouslyacquired data. The computing device 172 may be coupled to a display 182by which images, data, and user interfaces may be presented to aclinician before, after, and/or during a procedure.

Together, connector 164, cable 166, connector 168, interface 170, andconnection 174 facilitate communication between the one or more sensors,transducers, and/or other monitoring elements of the instrument 152 andthe computing device 172. However, this communication pathway isexemplary in nature and should not be considered limiting in any way. Inthat regard, it is understood that any communication pathway between theinstrument 152 and the computing device 172 may be utilized, includingphysical connections (including electrical, optical, and/or fluidconnections), wireless connections, and/or combinations thereof. In thatregard, it is understood that the connection 174 is wireless in someinstances. In some instances, the connection 174 includes acommunication link over a network (e.g., intranet, internet,telecommunications network, and/or other network). For example, in someembodiments the computing device 172 may be coupled to the interface 170by the network 180. In that regard, it is understood that the computingdevice 172 is positioned remote from an operating area where theinstrument 152 is being used in some instances. Having the connection174 include the connection to the network 180 can facilitatecommunication between the instrument 152 and the remote computing device172 regardless of whether the computing device is in an adjacent room,an adjacent building, or in a different state/country. Further, it isunderstood that the communication pathway between the instrument 152 andthe computing device 172 is a secure connection in some instances.Further still, it is understood that, in some instances, the datacommunicated over one or more portions of the communication pathwaybetween the instrument 152 and the computing device 172 is encrypted.

The system 150 also includes an instrument 175. In that regard, in someinstances instrument 175 is suitable for use as at least one ofinstruments 130 and 132 discussed above. Accordingly, in some instancesthe instrument 175 includes features similar to those discussed abovewith respect to instruments 130 and 132 in some instances. In theillustrated embodiment, the instrument 175 is a catheter-type device. Inthat regard, the instrument 175 includes one or more sensors,transducers, and/or other monitoring elements adjacent a distal portionof the instrument configured to obtain the diagnostic information aboutthe vessel. In the illustrated embodiment, the instrument 175 includes apressure sensor configured to monitor a pressure within a lumen in whichthe instrument 175 is positioned. The instrument 175 is in communicationwith an interface 176 via connection 177. In some instances, interface176 is a hemodynamic monitoring system or other control device, such asSiemens AXIOM Sensis, Mennen Horizon XVu, and Philips Xper IMPhysiomonitoring 5. In one particular embodiment, instrument 175 is apressure-sensing catheter that includes fluid column extending along itslength. In such an embodiment, interface 176 includes a hemostasis valvefluidly coupled to the fluid column of the catheter, a manifold fluidlycoupled to the hemostasis valve, and tubing extending between thecomponents as necessary to fluidly couple the components. In thatregard, the fluid column of the catheter is in fluid communication witha pressure sensor via the valve, manifold, and tubing. In someinstances, the pressure sensor is part of interface 176. In otherinstances, the pressure sensor is a separate component positionedbetween the instrument 175 and the interface 176. The interface 176 iscommunicatively coupled to the computing device 172 via a connection178.

Similar to the connections between instrument 152 and the computingdevice 172, interface 176 and connections 177 and 178 facilitatecommunication between the one or more sensors, transducers, and/or othermonitoring elements of the instrument 175 and the computing device 172.However, this communication pathway is exemplary in nature and shouldnot be considered limiting in any way. In that regard, it is understoodthat any communication pathway between the instrument 175 and thecomputing device 172 may be utilized, including physical connections(including electrical, optical, and/or fluid connections), wirelessconnections, and/or combinations thereof, and connections through thenetwork 180. In that regard, it is understood that the connection 178 iswireless in some instances. In some instances, the connection 178includes a communication link over a network (e.g., intranet, internet,telecommunications network, and/or other network) like the network 180.In that regard, it is understood that the computing device 172 ispositioned remote from an operating area where the instrument 175 isbeing used in some instances. Having the connection 178 include aconnection over the network 180 can facilitate communication between theinstrument 175 and the remote computing device 172 regardless of whetherthe computing device is in an adjacent room, an adjacent building, or ina different state/country. Further, it is understood that thecommunication pathway between the instrument 175 and the computingdevice 172 is a secure connection in some instances. Further still, itis understood that, in some instances, the data communicated over one ormore portions of the communication pathway between the instrument 175and the computing device 172 is encrypted.

It is understood that one or more components of the system 150 are notincluded, are implemented in a different arrangement/order, and/or arereplaced with an alternative device/mechanism in other embodiments ofthe present disclosure. For example, in some instances, the system 150does not include interface 170 and/or interface 176. In such instances,the connector 168 (or other similar connector in communication withinstrument 152 or instrument 175) may plug into a port associated withcomputing device 172. Alternatively, the instruments 152, 175 maycommunicate wirelessly with the computing device 172. Generallyspeaking, the communication pathway between either or both of theinstruments 152, 175 and the computing device 172 may have nointermediate nodes (i.e., a direct connection), one intermediate nodebetween the instrument and the computing device, or a plurality ofintermediate nodes between the instrument and the computing device.

Diagnostic information within a vasculature of interest can be obtainedusing one or more of instruments 130, 132, 152, and 175. For example,diagnostic information is obtained for one or more coronaries arteries,peripheral arteries, cerebrovascular vessels, etc. The diagnosticinformation can include pressure-related values, flow-related values,etc. Pressure-related values can include Pd/Pa (e.g., a ratio of thepressure distal to a lesion to the pressure proximal to the lesion), FFR(e.g. a ratio of the pressure distal to a lesion to the pressureproximal to the lesion under hyperemia), iFR (e.g., a ratio of thepressure distal to a lesion to the pressure proximal determined acrossthe wave-free period without hyperemia), etc. Flow-related values caninclude coronary flow reserve or CFR (e.g., maximum increase in bloodflow through the coronary arteries above the normal resting volume),basal stenosis resistance index (BSR), etc.

In some embodiments, the diagnostic information can include angiographicimages and/or other two-dimensional or three-dimensional depictions of apatient's vasculature. Such angiographic images may be accessed via thenetwork 180. For example, angiographic images of the patient'svasculature and/or associated models may be stored in a data center andaccessed by the computing device 172 for use during a procedure. Thediagnostic information and/or data obtained by instruments 130, 132,152, and/or 175 are correlated or co-registered to angiographic image(s)and/or other two-dimensional or three-dimensional depictions of apatient's vasculature. Co-registration can be completed using techniquesdisclosed in U.S. Pat. No. 6,930,014, titled “VASCULAR IMAGECO-REGISTRATION,” which is hereby incorporated by reference in itsentirety, based on the known pullback speed/distance, based on a knownstarting point, based on a known ending point, and/or combinationsthereof. In some embodiments, diagnostic information and/or data iscorrelated to vessel images using techniques similar to those describedin U.S. patent application Ser. No. 14/144,240, titled “DEVICES,SYSTEMS, AND METHODS FOR ASSESSMENT OF VESSELS” and filed on Dec. 30,2013, and which claims priority to U.S. Provisional Patent ApplicationNo. 61/747,480, titled “SPATIAL CORRELATION OF INTRAVASCULAR IMAGES ANDPHYSIOLOGICAL FEATURES” and filed Dec. 31, 2012, which are herebyincorporated by reference in their entirety. In some embodiments,co-registration and/or correlation can be completed as described in U.S.patent application Ser. No. 14/335,603, titled “DEVICES, SYSTEMS, ANDMETHODS FOR ASSESSMENT OF VESSELS” and filed on Jul. 19, 2013, and whichclaims priority to U.S. Provisional Patent Application No. 61/856,509,titled “DEVICES, SYSTEMS, AND METHODS FOR ASSESSMENT OF VESSELS” andfiled Jul. 19, 2013, which are hereby incorporated by reference in theirentirety.

Referring now to FIG. 5, shown therein is an exemplary depiction ofangiogram data as may be provided to the clinician in a user interface500, such as may be provided by the computing device 172 of FIG. 4.Other embodiments, of the present disclosure may be other imagingmodalities, such as magnetic resonance imaging (MRI), computedtomography (CT), etc. The user interface 500 includes a window 502 thatmay be presented in the display 182 as seen in FIG. 4. The windowdisplays angiogram data that includes cardiac tissue 506 and vasculature508 obtained using a contrast agent. In some embodiments, the windowdisplays CT data. In some embodiments, the angiogram 504 may be athree-dimensional angiogram that may be manipulated by the clinician toprovide different views, including different perspective views and/orcross-sectional views, of the patient's vasculature. During subsequentprocedures, the clinician may navigate the instruments 130 and/or 132through the patient's vasculature, collecting physiologic measurementstherein. The physiologic measurements may be stored in a memory of thecomputing device 172 and also displayed on the display 182. Theimage-based physiologic measurements may include a dominanceclassification, a degree of occlusion of a lesion, which may beexpressed as a percent diameter stenosis, a classification of a lesion,a degree of bending of a vessel of the vessel system, a length of alesion, and/or a degree of calcification of a lesion.

After obtaining the angiogram data, the data may be parsed by animage-processing component provided by the system 150 of FIG. 4 tosegment the patient's vasculature and estimate certain features thereof.The parsing of the data may be performed to extract image-basedphysiologic measurements that may be provided to a risk calculator togenerate a disease quantification score. This disease quantificationscore may be automatically performed, without the continued interactionof a clinician. For example, the image-based physiologic measurementsmay be extracted after an angiogram collection process is complete.Examples of risk calculators that may be used to generate the diseasequantification score are provided below.

When processing the angiogram data, quantitative coronary angiography(QCA) may be used to assess and identify blockages from the image-baseddata. A QCA process may be initiated automatically to identify anyblockages. While the clinician may provide a qualitative evaluationbased on his or her own experience, the information from the QCA processmay be used in subsequent steps to automatically generate an objectiveintervention recommendation. As is discussed in further detail below,co-registration techniques incorporated herein by reference and othersthat may be known to those of skill in the art may be used toco-register physiologic measurements to specific positions in a model ofthe patient's vasculature 508 generated from the angiogram 504 presentedin the window 502.

Referring now to FIG. 6, shown therein is a depiction of a userinterface 600 for evaluating a vessel based on obtained physiologicmeasurements (as depicted, pressure measurements, but may also includeflow volume, flow velocity, tissue characterization, and/or otherintravascular physiologic measurements or calculations based thereon)according to embodiments of the present disclosure. The user interfacemay be displayed on a touch-sensitive display. A clinician can view,analyze, and interact with the pressure data and/or visualrepresentations of the pressure data. As illustrated, the user interface600 is associated with a pressure ratio workflow, but other embodimentsof the user interface 600 may be associated with other modalities. Theuser interface 600 includes an FFR tab 604 and an iFR tab 602. The iFRtab 602 can include the obtained pressure measurements, and visualrepresentations of the pressure measurements. As shown, the iFR tab 602includes pressure waveform plots 612 and 638, both of which illustrateacquired pressure data over the same time period. The user interface 600also includes a window 614 that shows a calculated pressure ratio (e.g.,FFR, iFR, or otherwise).

In that regard, the pressure waveform plots 612 and 638 and thecalculated pressure ratio of user interface 600 illustrate aspects ofpressure measurements obtained as one instrument is moved through thevessel and another instrument is maintained at a fixed location. In thatregard, in some instances the pressure measurements are representativeof a pressure ratio between a fixed location within the vessel and themoving position of the instrument as the instrument is moved through thevessel. For example, in some instances a proximal pressure measurementis obtained at a fixed location within the vessel while the instrumentis pulled back through the vessel from a first position distal of theposition where the proximal pressure measurement is obtained to a secondposition more proximal than the first position (i.e., closer to thefixed position of the proximal pressure measurement).

For clarity in understanding the concepts of the present disclosure,this arrangement will be utilized to describe many of the embodiments ofthe present disclosure. However, it is understood that the concepts areequally applicable to other arrangements. For example, in someinstances, the instrument is pushed through the vessel from a firstposition distal of the proximal pressure measurement location to asecond position further distal (i.e., further away from the fixedposition of the proximal pressure measurement). In other instances, adistal pressure measurement is obtained at a fixed location within thevessel and the instrument is pulled back through the vessel from a firstposition proximal of the fixed location of the distal pressuremeasurement to a second position more proximal than the first position(i.e., further away from the fixed position of the distal pressuremeasurement). In still other instances, a distal pressure measurement isobtained at a fixed location within the vessel and the instrument ispushed through the vessel from a first position proximal of the fixedlocation of the distal pressure measurement to a second position lessproximal than the first position (i.e., closer the fixed position of thedistal pressure measurement).

The pressure differential between the two pressure measurements withinthe vessel (e.g., a fixed location pressure measurement and a movingpressure measurement) is calculated as a ratio of the two pressuremeasurements (e.g., the moving pressure measurement divided by the fixedlocation pressure measurement), in some instances.

The visual representations in the user interface 600 can illustrate thepressure ratio and/or the underlying pressure measurements in anysuitable way. Generally speaking, the representation of the data can beutilized to identify gradients/changes in the pressure ratio and/or theunderlying pressure measurements that can be indicative of a significantlesion in the vessel. In that regard, the visual representation of thedata can include the pressure measurement(s); a ratio of the pressuremeasurements; a difference in the pressure measurements; a gradient ofthe pressure measurement(s), the ratio of the pressure measurements,and/or the difference in the pressure measurements; first or secondderivatives of the pressure measurement(s), the ratio of the pressuremeasurements, and/or the difference in the pressure measurements; and/orcombinations thereof.

For example, the pressure waveform plots 612 and 638 show correspondingpressure data. In that regard, the pressure waveform plots 612 and 638can include the pressure waveform for the pressure sensing device movedthrough the vessel during the pullback, the pressure waveform for thestationary pressure sensing device, or both. In the illustratedembodiment, the pressure waveform plots 612 and 638 include the pressurewaveforms for both. In some instances the pressure waveform plot 612 isaugmented to highlight or otherwise accentuate the pressure datacorresponding to the diagnostic window utilized for the pressure ratiocalculations.

The pressure waveform plots 612 and 638 include time on the x-axis andmagnitude of pressure on the y-axis. The pressure waveform plot 638illustrates the obtained pressure measurements over a greater amount oftime compared to the waveform plot 612. For example, the pressurewaveform plot 638 illustrates the entire acquisition, pullback, or “run”while the pressure waveform 612 illustrates at least a portion thereof.As shown in FIG. 6, a user provides a touch input near seven seconds onthe pressure waveform plot 612. In response to the user touch input, theuser interface 600 can be modified to include one or more informationoverlays 660, 662, and/or 664. The overlay 660 is a vertical linehighlighting the time selected by the user by the touch input. Theoverlay 660 can be variously colored to visually distinguish theselected time. The overlay 664 provides the numerical value of the timethat is selected by the user touch input. The overlay 662 providespressure data at the selected time. In that regard, the overlay 662 caninclude a numerical value of a calculated pressure ratio (iFR, FFR,etc.) at the selected time, a numerical value of a compensated Pd/Pa atthe selected time, a numerical value of the average Pd value at theselected time, a numerical value of the average Pa value at the selectedtime, a numerical value of the actual Pd value at the selected time,and/or a numerical value of the actual Pd value at the selected time.The numerical values in the overlay 662 can be raw or modified values.When a particular time is highlighted in response to a user touch inputin the pressure waveform plot 612, the user interface 600 can beautomatically modified to include a corresponding overlay of the curve642 in the pressure waveform plot 638 to contextualize the highlightedtime within the entire acquisition. The user interface 600 also providespressure ratios 636 (e.g., iFR, compensated Pa/Pd values, etc.) at fixedintervals. For example, in FIG. 6, the iFR values 636 for each heartbeatcycle are displayed below the pressure waveform plot 612. In otherembodiments, the pressure ratios are displayed at various locationsrelative to the pressure waveform plot 612.

The user interface 600 also includes a window 614 that shows acalculated pressure ratio (e.g., FFR, iFR, or otherwise). In theillustrated embodiment of FIG. 6, the window 614 shows an iFR pressureratio value during a pullback. As shown in FIG. 6, the user interface600 provided on the display 182 includes a button 626 to allow aclinician to go back to a “Live” mode (or to toggle between a “Live”mode and a “Review” mode), in which the user interface 600, includingpressure waveform plots 612 and 638, calculated pressure ratios 636,and/or the windows 614, 670, 672 are updated in real time as a procedureis being performed. The record button 650 can be selected by a usertouch input on the bedside controller to begin storing the acquiredpressure data. When the user interface 600 is presented in “Review”mode, as shown in FIG. 6, the user interface 600 shows data obtainedpreviously. With respect to the “Live” mode, it should be noted that thedetermination of the diagnostic window and/or the calculation of thepressure differential are performed in approximately real time or liveto identify the diagnostic window of the heartbeat cycle and calculatethe pressure differential. In that regard, calculating the pressuredifferential in “real time” or “live” within the context of the presentdisclosure is understood to encompass calculations that occur within 10seconds of data acquisition. It is recognized, however, that often “realtime” or “live” calculations are performed within 1 second of dataacquisition. In some instances, the “real time” or “live” calculationsare performed concurrent with data acquisition. In some instances thecalculations are performed by a processor in the delays between dataacquisitions. For example, if data is acquired from the pressure sensingdevices for 1 ms every 5 ms, then in the 4 ms between data acquisitionsthe processor can perform the calculations. It is understood that thesetimings are for example only and that data acquisition rates, processingtimes, and/or other parameters surrounding the calculations will vary.In other embodiments, the pressure differential calculation is performed10 or more seconds after data acquisition. For example, in someembodiments, the data utilized to identify the diagnostic window and/orcalculate the pressure differential are stored for later analysis.

By comparing the calculated pressure differential to a threshold orpredetermined value, a physician or other treating medical personnel candetermine what, if any, treatment should be administered. In thatregard, in some instances, a calculated pressure differential above athreshold value (e.g., 0.80 on a scale of 0.00 to 1.00) is indicative ofa first treatment mode (e.g., no treatment, drug therapy, etc.), while acalculated pressure differential below the threshold value is indicativeof a second, more invasive treatment mode (e.g., angioplasty, stent,etc.). In some instances, the threshold value is a fixed, preset value.In other instances, the threshold value is selected for a particularpatient and/or a particular stenosis of a patient. In that regard, thethreshold value for a particular patient may be based on one or more ofempirical data, patient characteristics, patient history, physicianpreference, available treatment options, and/or other parameters.

In that regard, the coloring and/or other visually distinguishing aspectof the pressure differential measurements depicted in pressure ratios636 and/or window 614 of the user interface 600 of FIG. 6 are configuredbased on the threshold value in some instances. For example, a firstcolor (e.g., green, white, or otherwise) can be utilized to representvalues well above the threshold value (e.g., where the threshold valueis 0.80 on a scale of 0.00 to 1.00, values above 0.90), a second color(e.g., yellow, gray, or otherwise) can be utilized to represent valuesnear but above the threshold value (e.g., where the threshold value is0.80 on a scale of 0.00 to 1.00, values between 0.80 and 0.90), and athird color (e.g., red, black, or otherwise) can be utilized torepresent values equal to or below the threshold value (e.g., where thethreshold value is below 0.80 on a scale of 0.00 to 1.00, values ofbelow 0.80). It is appreciated that any number of color combinations,scalings, categories, and/or other characteristics can be utilized tovisually represent the relative value of the pressure differential tothe threshold value. However, for the sake of brevity Applicants willnot explicitly describe the numerous variations herein.

The user interface 600 includes an ECG waveform 632. The user interface600 additionally may include a patient name 666, patient identifier 668,and a date/time 674. The case log button 600 can be selected accessadditional information about the patient (e.g., other pressureacquisitions) and/or retrieve the current pressure acquisition data at alater time. A label field 634 allows the user to input additional notesregarding the patient or the procedure. Selecting the label field 634 bya touch input on the system can cause an on-screen keyboard to bedisplayed in the display 182. Other means of input, such as a mouse, akeyboard, voice-control, etc. may be used in other embodiments.

In obtaining physiology data, whether pressure or flow, etc. the datamay be obtained at regular intervals and displayed in the user interface600 according to those regular intervals. For example, each of the datasamples indicated by the lines in FIG. 6 may be obtained during apullback. When the rate of the pullback is known, a location of eachdata point may be co-registered with a specific location within thepatient's vasculature. Accordingly, physiologic measurements that arecollected using the instruments 130 and 132 may be associated withspecific locations within the patient's vasculature. While the exampleof pressure measurements is used often herein, in some embodiments,other physiology measurement data and/or imaging data may be collectedand co-registered. For example, IVUS data may be collected and processedto identify calcium deposits or plaques. Like pressure and/or flow data,this other information may be co-registered with the angiogram data suchthat the location of the calcium deposits may be depicted in connectionwith a model of the patient's vasculature in the display 182.

Referring now to FIG. 7, shown therein is a plurality of bifurcationlesions that may be detected and classified using imaging data, such asmay be provided by IVUS inspection. The imaging data may include anindication of whether an imaged surface is tissue, plaque, or a calciumdeposit. The bifurcation 700 includes a main vessel 702 and a sidevessel 704, and includes a stenosis 706 within the main vessel 702 onlyand positioned before the branching of the side vessel 704. Thebifurcation 710 depicts a stenosis 716 positioned within the main vessel702 only and after the branching of the side vessel 704. Bifurcation 720includes a stenosis 726 situated adjacent to the branching of the sidevessel 704, but limited to the main vessel 702. The stenosis 726includes portions both before and after the branching of the side vessel704 the bifurcation 730 includes a stenosis 736 that is situatedadjacent to the branching of the side vessel 704, similar to thestenosis 726. However, the stenosis 736 includes portions within theside vessel 704. The bifurcation 740 includes a stenosis 746 situatedwithin the side vessel 704 only. The bifurcation 750 includes a stenosis756 adjacent to the branching and including a portion before thebranching in the main vessel 702 and a portion after the branching inthe side vessel 704. The bifurcation 760 depicts a stenosis 766 havingportions proximate the branching and after the branching in both themain vessel 702 and the side vessel 704. Using IVUS data or othersuitable data, the system 150 may perform image-processing andimage-recognition to classify lesions occurring in each of the segmentsof interests. The segments may be labeled with the conventional namesfor each of the segments. Information regarding the segments, includingclassifications and associated severities, may be provided to a riskcalculator.

The risk calculator, whether a SYNTAX score calculator or anotherdisease quantification score calculator, may then provide a diseasequantification score. When the disease quantification score is above athreshold, the system 150 may recommend a CABG surgery is theappropriate intervention. When the disease quantification score is belowthe threshold the system 150 may recommend PCI. While risk calculators,such as the SYNTAX score calculator, have been available to clinicianspreviously, the system 150 provides for the automatic calculation anddetermination of the SYNTAX score or other such disease quantificationscore. Accordingly, the disease quantification score may be displayed tothe clinician during an assessment procedure.

Referring now to FIG. 8A, shown therein is an annotated depiction ofstylized images of a vessel according to embodiments of the presentdisclosure. The stylized user interface 800A of FIG. 8A may be presentedto a clinician in a display, as a window 801, and incorporates angiogramdata with an overlay of co-registered physiologic measurements asdescribed herein. As described herein, the physiologic measurementscollected using pressure sensors or other sensors may be co-registeredwith the angiogram data or, in some embodiments, with a two-dimensionalor three-dimensional model prepared therefrom. In other embodiments,angiogram data and the co-registered physiologic measurements may bepresented separately and not overlaid as illustrated. FIG. 8A includesstylized images 840 and 860 of the right coronary artery and of the leftcoronary artery, respectively. FIG. 8A further includes an index 820 forassessing the severity of one or more lesions and/or stenoses accordingto an embodiment of the present disclosure. FIG. 8A can be displayed ona display 182 of system 150 for assessing a patient's vasculature. Thatis, one or more components (e.g., a processor and/or processing circuit)of the system can render information, including angiogram data andphysiologic measurements, to provide display data to cause the displayof the images shown in FIG. 8A. In some embodiments, the representationsof the LCA 860 and the RCA 840 may be further stylized and/or presentedwithout the underlying angiogram data.

The images of the stylized vessels in FIG. 8A are annotated with one ormore visualizations configured to assist in identifying one or morelesions and/or stenoses, and/or assess the severity thereof. Theseannotations may be automatically provided by performingimage-recognition on angiogram data and/or other data, such as IVUSimaging data. The visualizations are based on physiology values obtainedfrom one or more instruments (e.g., instruments 130 and/or 132) as atleast one of the instruments is moved through the vessel. The stylizedvessels of FIG. 8A can be colorized and/or otherwise visualized using aheat map that illustrates changes in pressure measurements (or otherphysiologic measurements, such as flow volume, flow velocity, etc.)obtained as the instrument is moved through the vessel. Hatchings areused in FIG. 8A to represent such visualizations. In that regard, insome instances the pressure measurements shown in the heat map arerepresentative of a pressure differential between a fixed locationwithin the vessel and the moving position of the instrument as theinstrument is moved through the vessel. For example, in some instances aproximal pressure measurement is obtained at a fixed location within thevessel while the instrument is pulled back through the vessel from afirst position distal of the position where the proximal pressuremeasurement is obtained to a second position more proximal than thefirst position (i.e., closer the fixed position of the distal pressuremeasurement), such as is discussed herein in connection with FIG. 6.Accordingly, FIG. 8A includes depictions of co-registered physiologicmeasurements.

By comparing the calculated pressure differential to a threshold orpredetermined value, a clinician or other treating medical personnel candetermine what, if any, treatment should be administered. In thatregard, in some instances, a calculated pressure differential above athreshold value (e.g., 0.80 on a scale of 0.00 to 1.00) is indicative ofa first treatment mode (e.g., no treatment, drug therapy, etc.), while acalculated pressure differential below the threshold value is indicativeof a second, more invasive treatment mode (e.g., angioplasty, stent,etc.). In some instances, the threshold value is a fixed, preset value.In other instances, the threshold value is selected for a particularpatient and/or a particular stenosis of a patient. In that regard, thethreshold value for a particular patient may be based on one or more ofempirical data, patient characteristics, patient history, physicianpreference, available treatment options, and/or other parameters.

In that regard, the coloring and/or other visually distinguishing aspectof the physiology values (e.g., pressure differential measurements)depicted in FIG. 8 are configured based on the threshold value. Theseverity key or index 820 shows the colors 822 and their correspondingphysiological values 824. For example, a first color (e.g., green,medium grey, or otherwise) is utilized to represent values well abovethe threshold value (e.g., where the threshold value is 0.80 on a scaleof 0.00 to 1.00, values above 0.85), a second color (e.g., yellow,white, or otherwise) is utilized to represent values near but above thethreshold value (e.g., where the threshold value is 0.80 on a scale of0.00 to 1.00, values between 0.82 and 0.84), a third color (e.g.,orange, light grey, or otherwise) is utilized to represent values nearthe threshold value (e.g., where the threshold value is 0.80 on a scaleof 0.00 to 1.00, values between 0.79 and 0.81), and a fourth color(e.g., red, dark grey, or otherwise) is utilized to represent valuesequal to or below the threshold value (e.g., where the threshold valueis 0.80 on a scale of 0.00 to 1.00, values of 0.79 and below).

Area 832 of FIG. 8A indicates parts of the vessel with low severity(e.g., areas with a relatively high FFR value). Area 834 indicates partsof the vessel with greater severity compared to area 832 (e.g., areaswith a moderately high FFR value). Area 836 indicates parts of thevessel with a moderate severity (e.g., areas with a moderately low FFRvalue). Area 838 indicates parts of the vessel with a high severity(e.g., areas with a low FFR value). It is appreciated that any number ofcolor combinations, scalings, categories, and/or other characteristicscan be utilized to visually represent the relative value of the pressuredifferential to the threshold value. However, for the sake of brevityApplicants will not explicitly describe the numerous variations herein.

In some embodiments, the heat map included in FIG. 8A is based on acumulative or total pressure differential, where the color selected fora particular point is determined based on the pressure differentialbetween the instrument at that point being moved through the vessel andthe stationary or fixed instrument. In other embodiments, the heat mapis based on localized pressure differential, where the color selectedfor a particular point is determined based on differences between thepressure differential of that point with one or more of the surroundingpoints. In that regard, the localized pressure differential iscalculated as the difference between the immediately preceding point insome instances. For example, the localized pressure differential forpoint P_(n) is equal to the cumulative or total pressure differentialfor point P_(n) minus the total or cumulative pressure differential forpoint P_(n−1). In other instances, the localized pressure differentialis calculated as the difference between that point and a point a fixedamount of time (e.g., 10 ms, 5 ms, 2 ms, 1 ms, or otherwise) or distance(e.g., 10 mm, 5 mm, 2 mm, 1 mm, or otherwise) away from that point. Byutilizing a localized pressure differential the location of significantchanges in pressure differential values, which are often associated withthe presence of a lesion or stenosis, can be identified.

FIG. 8A includes transition points or areas of the vessel wherein thephysiology values between portions of the vessel change by a thresholdamount. In some embodiments, the threshold amount can be fixed, while inother embodiments, the threshold amount can vary between patients. Theone or more transition points can be indicated by visualizations. InFIG. 8A, the visualizations are markers 802. Markers 802 can bedescribed as tick marks. In some embodiments, markers 802 can extendtransversely across the vessel. In other embodiments, markers 802 cantake different shapes (e.g., circles, squares, etc.), be in differentpositions relative to the vessel (beside, within, etc.), be differentlysized, etc. The transition points can be representative of a boundary ofa lesion or stenosis of the vessel that results in an increased ordecreased pressure differential, which is illustrated by the change incolor of the vessel. As a result, one or more visualizations (e.g., thechange in color, markers 802, etc.) can be utilized to both identify thelocation of the lesion or stenosis within the vessel and assess theseverity of the lesion or stenosis. For example, under some conditions,the angiogram data may appear to show a normal vessel, while thephysiologic measurements presented in the heat map (and shown overlaidon the angiogram data in the user interface 800A) may provide additionalinformation. Similarly, while the angiogram data may provide a basis fora disease quantification score, the incorporation of the physiologicmeasurements obtained within the vessels provides a broader basis forthe functional disease quantification score.

FIG. 8A includes visualizations for providing diagnostic informationcollected by one or more instruments at a corresponding location of thevessel on the display. In that regard, value indicators 804 can bedisposed adjacent to markers 802 to indicate the location within thepatient's vasculature to which the measurement corresponds. In otherembodiments, value indicators 804 are displayed further away frommarkers 802, but an additional visual element (e.g., an arrow, astraight line, a curved line, marker 802 and value indicator 804 are thesame or similar colors, etc.) is provided to indicate the location ofthe measurement. In some embodiments, the value indicators 804 includeonly the value of the physiological measurement (e.g., “0.96”), while inother embodiments, the value indicators 804 include the value and typeof physiological measurement (e.g., “0.95 FFR”). In yet otherembodiments, additional information, such as the time the measurementwas taken, severity of the stenosis or lesion, etc. can also beprovided. For example, a user may provide a user input (e.g., aselection from a drop-down menu, toggle through the available options,etc.) selecting the types of information that should be displayed invalue indicators 804. Labels 806, for each of the value indicators 804,can also be provided. Labels 806 can include alphabetical, numeric,and/or other symbolic characters. Labels 806 may assist in identifyingmarkers 802 and/or value indicators 804 (e.g., to distinguish betweendifferent markings/value indicators and/or to facilitate discussion ofthe vessel depictions).

In some embodiments, markers 802 and/or value indicators 804 can bepositioned automatically based on the physiologic measurements. Thesystem can be configured to select locations within the vessel that areclinically significant based on the diagnostic information (e.g.,locations where the physiologic measurements change significantly, suchas points at which pressure changes). Similarly, the one or morevisualizations of FIG. 8A can include labels 814 and/or labels 816 forvarious predefined segments of the patient's vasculature. These labels814 and 816 may also be automatically generated based on the angiogramdata using image-recognition and modeling techniques. Labels 816 can betextual indications providing the names of major and/or minor vessels orsegments thereof. Labels 814 can include alphabetical, numeric, and/orother symbolic characters. In some embodiments, labels 814 cancorrespond to a listing of parts of patient's vasculature. For example,labels 814 can be based on parts of the patient's vasculature asidentified according to one or more risk calculators. The segmentsidentified by labels 814 and/or 816 include, but are not limited to,right coronary artery (RCA), left main coronary artery, circumflexcoronary artery, left anterior descending (LAD), RCA proximal, RCA mid,RCA distal, LAD proximal, LAD mid, LAD apical, first diagonal,additional first diagonal, second diagonal, additional second diagonal,proximal circumflex, intermediate/anterolateral, obtuse marginal, distalcircumflex, left posterolateral, posterior descending, among others. Insome embodiments, the labels 814 and 816 are included automatically bythe system 150 upon performing an image-recognition process on theangiogram information such as that depicted in the user interface 500 ofFIG. 5. The angiogram information may include, informationcharacterizing or describing features of the vessel system such as thecontours, location, branches, and other features of the vessel(s) toautomatically identify individual vessels within the patient'svasculature. In this way, a model of the patient's vasculature may begenerated and parsed to identify specific sections warranting theappropriate label. While abbreviations and particular vessels are usedin FIG. 8A, it is understood that any suitable label can be used.

These labels 814 and 816 may also be used by the system 150 ingenerating a disease quantification score. For example, the diseasequantification score may be a SYNTAX score such as that described inGeorgios Sianos, et al., The SYNTAX Score: and angiographic tool gradingthe complexity of coronary artery disease, Eurolntervention; v.2005;1:219-227, which is incorporated by reference herein in its entirety.For example, where the patient's vasculature being observed is thepatient's coronary tree, the system 150 may parse angiographic data toidentify segments that may then be analyzed individually to collect dataand insert into a risk calculator such as that available atwww.syntaxscore.com, that operates on segment-specific data. In variousembodiments, the risk calculator can include one or more algorithms forcalculating the likelihood of mortality, the likelihood of success whentreating the lesion or stenosis, etc. The disease quantification scoremay be based on the provided data and any additional relevant patienthistory. The provided data and/or patient history can include binary(e.g., yes or no) and/or continuous (e.g., percentage of narrowing ofthe vessel) values. The provided data may be based on measureddiagnostic information. The provided data can include one or more ofexistence of mitral stenosis, existence of aortic stenosis, existence oftotal occlusion, existence of trifurcation and how many diseasedsegments involved, existence of bifurcation, existence of aorto ostiallesion, existence of severe tortuosity in the vessel, whether length ofthe lesion is greater than 20 mm or another length, existence of heavycalcification, existence of thrombus, if and which segments arediffusely diseased and/or narrowed, number of lesions, percentage ofnarrowing, involvement of proximal LAD lesion, etc. Other relevantpatient history can include one or more of age; gender; whether thepatient has diabetes, hypertension, hypercholesterolemia, peripheralvascular disease; whether the patient is currently smoking; whether thepatient has a positive family history of heart disease; whether thepatient has had a previous myocardial infarction and/or previous PCI;the ventricular ejection fraction percentage, etc. The risk calculatormay output a quantity that is an objective measure of the riskassociated with the patient's condition based upon the provided imagingdata, non-invasive physiologic measurements, and patient history.

Some embodiments of the risk calculator may include a fractional flowreserve (FFR)-guided SYNTAX score (SS) or functional SYNTAX score (FSS),as described in Chang-Wook Nam, et al., Functional SYNTAX Score for RiskAssessment in Multivessel Coronary Artery Disease, Journal of theAmerican College of Cardiology 2011; 58(12): 1211-1218, which isincorporated by reference herein in its entirety. As used herein, the“functional SYNTAX score” includes SYNTAX scores that incorporate FFRdata, iFR, and/or other types of physiology measurement data. Incalculating the disease quantification score, information may beobtained from externally obtained images, such as angiogram data andfrom previously obtained patient health information, includingpreviously performed examinations. In using the risk calculator todetermine the disease quantification score, obstructions in the labeledsegments (labeled with the labels 814) may be analyzed forclassification and for assessment of severity.

The user interface 800A may further include a disease quantificationscore window 870 that communicates the patient's disease quantificationscore to the clinician. Additionally, a functional diseasequantification score is also presented in a functional diseasequantification score window 872. This functional disease quantificationscore may be derived using the co-registered physiologic measurements tofurther inform the disease quantification score. Such co-registeredphysiologic measurements may include measurements such as FFR and/or iFRmeasurements. The co-registered physiologic measurements may be used toadjust the inputs to the risk calculator. For example, when thephysiologic measurements indicate that a lesion automatically detectedfrom the angiogram data causes an insignificant pressure drop within thevasculature, a factor may be added to the inputs to the risk calculatorto more appropriately weigh the corresponding lesion. For example, asshown in the window 801, pressure drops are observed between point A andpoint B, between points C and D, and between points D and E. Each ofthese pressure drops may be associated with a specific lesion that maybe identified from visual data, such as externally obtained angiogramdata and/or internally obtained IVUS data. While the visual data mayprovide sufficient information to obtain a disease quantification score,the physiology data may indicate the relative significance of eachidentified lesion. For example, the drop caused by a lesion betweenpoints D and E may be indicated as less significant by the physiologicmeasurements. Accordingly, data entered into the risk calculator that isassociated with the lesion between points D and E may be given lessweight by the addition of a mitigating factor.

As shown in the functional disease quantification score window 872, thismitigating factor results in a functional disease quantification scoreof 21. In some embodiments, the functional disease quantification scoremay be continuously displayed while physiologic measurements areobtained. The functional disease quantification score may becontinuously or periodically updated as new physiologic measurements arecollected and processed to determine their effect on the traditionaldisease quantification score. Alternatively, the clinician could press abutton on the display or on another input mechanism to request that thefunctional disease quantification score be updated. While the diseasequantification score of 35, shown in the disease quantification scorewindow 870 may indicate that a CABG surgery is the appropriate course oftreatment, the functional disease quantification score, whichincorporates additional physiology data, may indicate that PCI is a moreappropriate intervention for the patient. Accordingly, in somesituations where the disease quantification score is above a thresholdvalue, the functional disease quantification score may be below thatvalue, and thereby recommend a different intervention.

As shown in FIG. 8A, an intervention recommendation window 874 isincluded. The intervention recommendation window 874 may provide avisual recommendation of either CABG or PCI depending on the data. Oneor more images of a vessel, the visualizations in those images, and/orthe measured physiological values can be used to evaluate whether toperform a first surgical procedure or a second surgical procedure. Forexample, the first surgical procedure can be a CABG and the secondsurgical procedure can be PCI.

The one or more visualizations of FIG. 8A can include or be supplementedwith information regarding characteristics of the lesion or stenosisand/or the vessel using one or more other vessel data-gatheringmodalities. The other representations of the lesion or stenosis and/orthe vessel can include, e.g., IVUS (including virtual histology), OCT,ICE, Thermal, Infrared, flow, Doppler flow, and/or other vesseldata-gathering modalities. The additional information can provide a morecomplete and/or accurate understanding of the vessel characteristicsand/or assist in evaluating a risk associated with a lesion or stenosis.For example, in some instances the information can include the occlusivevalue of the vessel. The occlusive value of the vessel and/or otheradditional information may be utilized to calculate an objective measureof the risk associated with the stenosis or lesion.

It is understood that numerous other visualization techniques may beutilized to convey the information of FIG. 8A in the context of anangiographic image or other image of the vessel (including bothintravascular and extravascular imaging techniques, such as IVUS, OCT,ICE, CTA, etc.) to help the user evaluate the vessel. In that regard,while the examples of the present disclosure are provided with respectto angiographic images, it is understood that the concepts are equallyapplicable to other types of vessel imaging techniques, includingintravascular and extravascular imaging

In some instances, a user is able to select what information should beincluded or excluded from the displayed image. In that regard, it shouldbe noted that these visualization techniques related to conveying thepressure measurement data in the context of an angiographic or otherimage of the vessel can be utilized individually and in anycombinations. For example, in some implementations a user is able toselect what visualization mode(s) and/or portions thereof will beutilized and the system outputs the display accordingly. Further, insome implementations the user is able to manually annotate the displayedimage to include notes and/or input one or more of the measuredparameters.

The images of vessels in FIG. 8A can include three-dimensional,two-dimensional, angiographic, a computed tomography angiographic (CTA),and/or other suitable forms of images. In some embodiments, athree-dimensional image may be rotated about a vertical axis. In someembodiments, a two-dimensional image may include multiple views about avertical axis such that different two-dimensional views are shown whenthe image is rotated. In some implementations, the three dimensionalmodel is displayed adjacent to a corresponding two dimensional depictionof the vessel. In that regard, the user may select both the type ofdepiction(s) (two dimensional (including imaging modality type) and/orthree dimensional) along with what visualization mode(s) and/or portionsthereof will be utilized. The system will output a corresponding displaybased on the user's preferences/selections and/or system defaults.

FIG. 8B is a diagram of a user interface 800B that includesvisualizations for providing diagnostic information collected by one ormore instruments at a corresponding location of the vessel on thedisplay. The user interface 800B includes many of the features describedherein in connection with the user interface 800A of FIG. 8A. The window801 of the user interface 800B presents an angiographic image withoverlaid data. While the user interface 800A includes pressure data, theuser interface 800B displays markers 802 that divide the vasculatureinto segments according to the risk calculator used to derive thedisease quantification score. In proximity to teach of the segmentsbetween the markers 802, is a disease quantification score (DSQ)indicator 852 that visually depicts the disease quantification scorecontribution of the associated segment. A function DSQ indicator 854 mayalso be presented in proximity to the segment to communicate thefunctional disease quantification score contributed associated with thesegment. The segmentation may be performed according to the particulardisease quantification score approach being implemented. For example,the segments may correspond to the segmenting used in the SYNTAX score,as described herein. In other embodiments, the representations of thecontributions may be provided in colors, as used in the user interface800A. A pressure data view button 876 may be provided in the userinterface 800B to revert to the user interface 800A. A correspondingbutton may be present in some embodiments of the user interface 800A toswitch the DSQ view of user interface 800B.

FIG. 9 is a flow diagram of a method 900 for recommending anintervention according to an embodiment of the present disclosure.Method 900 can be implemented by a system described herein, such assystem 150 of FIG. 4. As illustrated in FIG. 9, the method 900 isillustrated as a plurality of enumerated steps or operations.Embodiments of the method 900 may include additional steps or operationsbefore, after, in between, or as part of the enumerated steps. At step902, the method 900 includes obtaining image data from an image of avessel system. This may be done by contacting networked storage such asan electronic health record storage system to obtain data such asangiogram data. The angiogram data may include a two dimensionalangiographic image, a three dimensional angiographic image, and/or acomputed tomography (CT) angiographic image. An example of the angiogramdata may be seen in the user interface 500 of FIG. 5, which includes theangiogram 504. At step 904, the method 900 may include obtainingphysiologic measurements from a first instrument and a second instrumentpositioned within the vessel of the patient while the second instrumentis moved longitudinally through the vessel from a first position to asecond position. One or more diagnostic measurements (e.g.,pressure-based including FFR and iFR, flow-based including CFR, etc.)can be used to gather the physiologic measurements to characterize theexistence and/or severity of a lesion or lesions within the vasculatureof a patient. For example, when FFR is used, areas of a patient'svasculature that have a relatively high FFR (e.g., greater than 0.80)are characterized as not having a lesion or stenosis, while areas with arelatively low FFR (e.g., less than 0.80) are characterized as having alesion or stenosis. The severity can be evaluated based on the heat mapdescribed herein. The physiologic measurements may be obtained in amanner that provides at least some location information associated withthe measurements.

At step 906, the method 900 includes co-registering the physiologicmeasurements with the image data to produce co-registered physiologicmeasurements. The co-registered physiologic measurements can bedisplayed in an overlaid fashion, such that the physiologic measurementsmay be visualized in association with the angiogram image data. Anexample may be seen in the user interface 800A of FIG. 8A. Byco-registering the physiologic measurements with the image data, thesystem 150 may provide additional perspective to a clinician orclinicians. The window 1102 may indicate the physical dimensions of thepatient's vasculature, which may be sufficient to identify one or morelesions therein, while the physiologic measurements indicate the impactor effect of lesions with the vasculature. In some embodiments,co-registering the physiologic measurements with the image data mayinclude associating, in a data file, each physiology measurement with alocation within the vessel system, identifying a corresponding locationfor each physiology measurement with the image data, and associating inthe co-registered physiologic measurements data file, each physiologymeasurement with its corresponding location within the image of thevessel system. In some embodiments, co-registering the physiologicmeasurements may produce a new data file that includes the co-registeredphysiologic measurements.

At step 908, the method 900 includes determining whether to perform afirst surgical procedure over a second surgical procedure, wherein thedetermining is based on the co-registered physiologic measurements. Thedetermination may result in a recommendation of the intervention for thepatient. For example, the intervention recommendation may be to performeither a CABG operation or a PCI operation. As part of the method 900,an indication of the intervention recommendation may be displayed to aclinician in a display, at step 910. As illustrated, the indication is atext-based indication. In other embodiments, another form of indicationmay be included.

The determining whether to perform the first surgical procedure or thesecond surgical procedure may include steps or operations ofinterpreting the image data of the vessel system, identifying one ormore lesions within the vessel system, and extracting physiologyinformation. The physiology information may include dimensions andlocations of vessels, and may further include a dominanceclassification, a degree of occlusion of the lesion, a classification ofthe lesion, a degree of bending of a vessel of the vessel system, alength of the lesion, a degree of calcification of the lesion, etc. Indetermining whether to perform the first surgical procedure or thesecond surgical procedure, the method 900 may include calculating adisease quantification score from the extracted physiology information.This disease quantification score may be an image based score obtainedby processing image data to provide inputs to a risk calculator.Additionally, the risk calculator may receive patient historyinformation as an input.

In some embodiments of the method 900, evaluating whether to perform thefirst surgical procedure or the second surgical procedure furtherincludes modifying or transforming the image-based diseasequantification score based on the co-registered physiologic measurementsto produce a functional disease quantification score. A functionaldisease quantification score may be lower than the image-based diseasequantification score. For example, the co-registered physiologicmeasurements may indicate that a lesion identified from the image datamay have less impact on the patient's vasculature than would beestimated from the image based on a clinician's experience alone.Accordingly, the use of the functional disease quantification score mayprevent unnecessary CABG operations. In some embodiments, theimage-based disease quantification score may be a SYNTAX score, whilethe functional disease quantification score includes a functional SYNTAXscore. As part of the method 900, the disease quantification score, thefunctional disease quantification score, and/or an associatedintervention recommendation may be displayed. In some embodiments, theintervention recommendation may be based on whether the functionaldisease quantification score is above a threshold value. For example,when the functional disease quantification score is above a thresholdvalue of 30, the intervention recommendation may be for a CABGoperation. When the functional disease quantification score is below thethreshold value, intervention recommendation may be for a PCI procedure.The threshold value may be 30, 25, or another value suitable as thebasis for intervention recommendation. For example, if the thresholdvalue were 20, then the functional disease quantification score shown inthe window 872 would be above the threshold value and the indication ofthe recommended intervention shown in the window 874 of FIG. 8A would bean indication to perform a CABG operation, rather than PCI.

As part of the evaluating whether to perform the first surgicalprocedure or the second surgical procedure, the regions of the patientanatomy and associated severity are provided to a risk calculator. Theseregions of the patient anatomy may be automatically segmented by imageprocessing performed on the angiogram data. Similarly, image data may beprocessed to estimate the associated severity of any lesions in thesegmented regions. In various embodiments, the risk calculator caninclude one or more algorithms for calculating the likelihood ofmortality, the likelihood of success when treating the lesion orstenosis, etc. The risk calculator may output a quantity that is anobjective measure of the risk associated with the patient's condition.The risk calculator may include a SYNTAX score or a fractional flowreserve (FFR)-guided SYNTAX score (SS) or functional SYNTAX score (FSS),as described in Chang-Wook Nam, et al., Functional SYNTAX Score for RiskAssessment in Multivessel Coronary Artery Disease, Journal of theAmerican College of Cardiology 2011; 58(12): 1211-1218, which isincorporated by reference herein in its entirety. The risk calculatormay also include any modified SYNTAX score or any numerical or otherwiseobjective disease quantification score that incorporates physiologicmeasurements, including, but not limited to, flow-based (CFR, etc.)and/or pressure-based (FFR, iFR, etc.) parameters. The risk calculatormay also generate an indication of perfusion benefit and an indicationof graft patency. For example, the risk calculator may quantify thepredicted perfusion change should CABG be selected as therevascularization strategy.

Referring now to FIG. 10, shown therein is a flow chart of anothermethod for generating an intervention recommendation for treating avessel of a patient. In the illustrated embodiment, the method 1000 maybegin in step 1002 in which a set of pressure measurements taken withina vessel system of the patient is co-registered with image data of thevessel system to produce co-registered pressure measurements. Aprocessing system like the system 150 may receive data sets that includethe image data and the pressure measurements and co-register them. Thismay be done by generating a co-registered pressure measurements datafile that includes information linking a pressure measurement to alocation within the vessel system or a three-dimensional model thereof.

In step 1004, the processing system calculates an image-based diseasequantification score from the image data of the vessel system. Thisimage-based disease quantification score may be a SYNTAX score asdescribed herein. In step 1006, the processing system modifies theimage-based disease quantification score based on the co-registeredphysiologic measurements to produce a functional disease quantificationscore. This functional disease quantification score may be a functionalSYNTAX score, or a SYNTAX score that incorporates functional,physiologic measurements, such as pressure, flow, etc., as describedherein.

In step 1006, the processing system determines whether to perform apercutaneous coronary intervention or a coronary artery bypass graft,wherein the determining is based on the functional diseasequantification score. For example, when the functional diseasequantification score is below a threshold, the processing system maydetermine that a PCI should be performed. When the functional diseasequantification score is above the threshold, the processing system maydetermine that a CABG surgery should be performed. An indication of therecommendation intervention may be displayed on a display, in step 1008,although in some embodiments, the indication may be communicated inother ways as described herein.

Embodiments of the present disclosure may enable objectiverecommendations to be provided to a clinician to decide betweentreatment approaches. While many of the embodiments here are directed todetermining whether to perform a first procedure or a second procedure,some embodiments of the disclosure may be directed to determiningwhether to perform a first procedure or no procedure or whether toperform a first procedure, a second procedure, or not procedure. Yetother embodiments may be directed to determining objectively whether toperform a procedure, and then determining which of two or more optionsto recommend based on multiple sources of data provided to a riskcalculator. In some embodiments, the systems and methods may recommendboth a PCI procedure and a CABG surgery. For example, a PCI proceduremay be recommend for a left coronary artery, while a CABG procedure isrecommended for a right coronary artery.

Persons skilled in the art will also recognize that the apparatus,systems, and methods described above can be modified in various ways.Accordingly, persons of ordinary skill in the art will appreciate thatthe embodiments encompassed by the present disclosure are not limited tothe particular exemplary embodiments described above. In that regard,although illustrative embodiments have been shown and described, a widerange of modification, change, and substitution is contemplated in theforegoing disclosure. It is understood that such variations may be madeto the foregoing without departing from the scope of the presentdisclosure. Accordingly, it is appropriate that the appended claims beconstrued broadly and in a manner consistent with the presentdisclosure.

What is claimed is:
 1. A method of evaluating a vessel system of apatient to recommend an intervention for the patient, the methodcomprising: obtaining, at a processor, pressure measurements from apressure-sensing instrument and a pressure-sensing guidewire positionedwithin a vessel of the patient while the pressure-sensing guidewire ismoved longitudinally through the vessel from a first position to asecond position, the pressure-sensing guidewire comprising a proximalportion, a distal portion, and a pressure sensor coupled to the distalportion; determining, based on the pressure measurements, a plurality ofpressure ratios along a length of the vessel with a lesion, wherein thelength of the vessel comprises a first plurality of locations defining afirst segment and a second plurality of locations defining a secondsegment; obtaining, at the processor, external image data of the vessel;co-registering, with the processor, the plurality of pressure ratioswith the external image data to produce first co-registered pressureratios having a positional relationship with the first plurality oflocations and second co-registered pressure ratios having the positionalrelationship with the second plurality of locations; determining, withthe processor, first image-based physiologic measurements associatedwith the first segment and second image-based physiologic measurementsassociated with the second segment, from the external image data;calculating, with the processor, a first functional diseasequantification score associated with the first segment and a secondfunctional disease quantification score associated with the secondsegment, wherein the calculating comprises: determining a firstimage-based disease quantification score based on the first image-basedphysiologic measurements and a second image-based disease quantificationscore based on the second image-based physiologic measurements; andmodifying the first image-based disease quantification score by a firstfactor to generate the first functional disease quantification score andthe second image-based disease quantification score by a second factorto generate the second functional disease quantification score, whereinthe first factor is determined based on the first co-registered pressureratios such that the first functional disease quantification score isattributable to the positional relationship between the firstco-registered pressure ratios and the first plurality of locations, andwherein the second factor is determined based on the secondco-registered pressure ratios such that the second functional diseasequantification score is attributable to the positional relationshipbetween the second co-registered pressure ratios and the secondplurality of locations; and outputting, to a display in communicationwith the processor, a graphical representation of the first functionaldisease quantification score, the second functional diseasequantification score, the first image-based disease quantificationscore, and the second image-based disease quantification score.
 2. Themethod of claim 1, wherein the external image data of the vesselcomprises at least one of a two-dimensional angiographic image, athree-dimensional angiographic image, or a computed tomography (CT)angiographic image.
 3. The method of claim 1, wherein co-registering theplurality of pressure ratios with the external image data comprises:associating, in a data file, each pressure ratio with a location withinthe vessel; identifying a corresponding location for each pressure ratiowithin the external image data; and associating, in a co-registeredpressure ratios data file, each pressure ratio with its correspondinglocation within the external image data of the vessel.
 4. The method ofclaim 1, wherein at least one of the first functional diseasequantification score or the second functional disease quantificationscore indicates whether to perform a first surgical procedure or asecond surgical procedure, and wherein determining whether to performthe first surgical procedure or the second surgical procedure comprises:interpreting, by the processor, the external image data of the vessel;and identifying one or more lesions within the vessel.
 5. The method ofclaim 1, wherein the first image-based physiologic measurements and thesecond image-based physiologic measurements comprise at least one of adominance classification, a degree of occlusion of the lesion, aclassification of the lesion, a degree of bending of the vessel, alength of the lesion, a location of the lesion, or a degree ofcalcification of the lesion.
 6. The method of claim 1, wherein the firstfunctional disease quantification score and the second functionaldisease quantification score is determined further based on patienthistory information.
 7. The method of claim 1, further comprising:outputting, to the display, a recommendation for a procedure when atleast one of the first functional disease quantification score or thesecond functional disease quantification score is below a threshold. 8.The method of claim 1, wherein the first image-based diseasequantification score and the second image-based disease quantificationscore comprise a SYNTAX score.
 9. The method of claim 1, wherein atleast one of the first functional disease quantification score or thesecond functional disease quantification score indicates whether toperform a first surgical procedure or a second surgical procedure, andwherein the first surgical procedure comprises a percutaneous coronaryintervention and the second surgical procedure comprises a coronaryartery bypass graft.
 10. A system for generating an interventionrecommendation for treating a vessel of a patient, comprising: apressure-sensing guidewire comprising a proximal portion, a distalportion, and a pressure sensor coupled to the distal portion; and aprocessor in communication with the pressure-sensing guidewire, theprocessor configured to: obtain pressure measurements from apressure-sensing instrument and the pressure-sensing guidewire while thepressure-sensing guidewire is positioned within the vessel of thepatient and moved longitudinally through the vessel from a firstposition to a second position; determine, based on the pressuremeasurements, a plurality of pressure ratios along a length of thevessel with a lesion, wherein the length of the vessel comprises a firstplurality of locations defining a first segment and a second pluralityof locations defining a second segment; obtain external image data ofthe vessel; co-register the plurality of pressure ratios with theexternal image data to produce first co-registered pressure ratioshaving a positional relationship with the first plurality of locationsand second co-registered pressure ratios having the positionalrelationship with the second plurality of locations; determine, from theexternal image data, first image-based physiologic measurementsassociated with the first segment and second image-based physiologicmeasurements associated with the second segment; calculate a firstfunctional disease quantification score associated with the firstsegment and a second functional disease quantification score associatedwith the second segment; and output, to a display, a graphicalrepresentation of a first image-based disease quantification score, asecond image-based disease quantification score, the first functionaldisease quantification score, and the second functional diseasequantification score, wherein, to calculate the first functional diseasequantification score and the second functional disease quantificationscore, the processor is configured to: determine the first image-baseddisease quantification score based on the first image-based physiologicmeasurements and the second image-based disease quantification scorebased on the second image-based physiologic measurements; and modify thefirst image-based disease quantification score by a first factor togenerate the first functional disease quantification score and thesecond image-based disease quantification score by a second factor togenerate the second functional disease quantification score, wherein thefirst factor is determined based on the first co-registered pressureratios such that the first functional disease quantification score isattributable to the positional relationship between the firstco-registered pressure ratios and the first plurality of locations, andwherein the second factor is determined based on the secondco-registered pressure ratios such that the second functional diseasequantification score is attributable to the positional relationshipbetween the second co-registered pressure ratios and the secondplurality of locations.
 11. The system of claim 10, further comprising amemory in communication the processor, wherein the external image dataof the vessel comprises at least one of a two-dimensional angiographicimage, a three-dimensional angiographic image, or a computed tomographyangiographic (CTA) image, and wherein the external image data is storedin the memory.
 12. The system of claim 10, wherein, to co-register theplurality of pressure ratios with the external image data, the processoris further configured to: associate, in a data file, each pressure ratiowith a location within the vessel; identify a corresponding location foreach pressure ratio within the external image data; and associate, in aco-registered pressure ratio data file, each pressure ratio with itscorresponding location within the external image data of the vessel. 13.The system of claim 10, wherein the processor is further configured to:identify one or more additional vessels from the external image data;and identify one or more lesions within the one or more additionalvessels.
 14. The system of claim 10, wherein the first image-basedphysiologic measurements and the second image-based physiologicmeasurements comprise at least one of a dominance classification, adegree of occlusion of the lesion, a classification of the lesion, adegree of bending of the vessel, a length of the lesion, a location ofthe lesion, or a degree of calcification of the lesion.
 15. The systemof claim 10, wherein the processor calculates is configured to calculatethe first functional disease quantification score and the secondfunctional disease quantification score further based on patient historyinformation.
 16. The system of claim 10, wherein the processor isfurther configured to: obtain additional pressure measurements from thepressure-sensing instrument and the pressure-sensing guidewire; andmodify at least one of the first functional disease quantification scoreor the second functional disease quantification score based on theadditional pressure measurements.
 17. The system of claim 16, whereinthe first image-based disease quantification score and the secondimage-based disease quantification score comprise a SYNTAX score. 18.The system of claim 10, wherein the graphical representation of thefirst functional disease quantification score and the second functionaldisease quantification score comprises a numerical value.
 19. The methodof claim 1, wherein the graphical representation of the first functionaldisease quantification score and the second functional diseasequantification score comprises a numerical value.
 20. The system ofclaim 10, wherein at least one of the first factor or the second factorfurther corresponds to a relative effect on blood flow within the vesselof a first lesion compared to a second lesion.